Thanks BurrWalnut for your prompt reply.

Unfortunately the problem persists after trying all of your suggestions. I did in fact try the fsutil resource setautoreset true c:\ option before I posted on here.

I ran the chkdisk /f /r without an obvious problem, then the sfc /scannow which still shows the 98% with corrupt files found . . . etc. Needless to say the Updating issue is still there.

I'd be grateful if you could guide me through the repair procedure. The machine is an Acer Aspire (Vista Home Premium) and have been given 2 DVD's which if I remember rightly, when you first set the Acer's up from new, asks you if you want to create your recovery discs. I presume this is what they are with looking. They are not official ACER DVD's.

I hope we can repair without going down the reformat route and losing data as it is someone else's machine.

Many thanks for your patience.